Method and apparatus for feeding liquid fuel to internal combustion engines



Aug. 22, 1933. a... o. FRENCH METHOD AND APPARATUS FOR FEEDIEIG' LIQUID FUEL To INTERNAL COMBUSTION ENGINES Filed April 15, 1929 I Patented Aug. 22, I933 UNITED STATES PATENT? OFFICE ENGINES Louis 0. French,

Milwaukee, Wis.

Application April 15, 1929. Serial No. 355,208

14 Claims.

The invention relates to a method and apparatus for feeding liquid fuel to and forming combustible mixtures of fuel and air in internal combustion engines.

- Internal combustion engines may be classified in two general classes-carburetor type engines and injection type engines. In carburetor type engines the mixture is prepared outside the cylinder and the compression pressure is limited to a relatively low amount. In injectiofi type engines some form of metering valve or pump associated with a spray nozzle or a metering valve associated with a chamber in the engine, provided with small holes,- is used to introduce the fuelinto the engine. In this latter class, owing to the metering of the fuel by pumps and needle valves, the fuel usually being under high pressure, there are limits to the smallness of the amount of fuel that can bereadily handled. Furthermore, in both the carburetor and injection type engines the danger of clogged nozzles or small metering passages is ever present. The object of the present invention is to provide a novel method of supplying liquid fuel to and combining it with the air in internal combustion engines, whereby the fuel is delivered to the com-' bustion chamber of the engine in the form of a non-kinetic film which on being acted upon 1 by the air in said chamber moving over said film is vaporized and mixed with the air to form a combustible mixture. By this method relatively large fuel supply passages may be used, which eliminates the danger of clogging, and very small amounts of fuel can be handled with relatively large parts so that liquid fuel can be readily supplied before the end of the compression stroke to engines of small size, for example two or three inch bore, such as are used for outboard motors, whereby the compression pressure in such engines can beincreased with a resulting increase in effic'iency.

A further object of the invention is to provide simple mechanism for carrying out the method including a: movable member which at one point, sealed from the combustion chamber of the engine, receives liquid fuel and at another point of its movement exposes the fuel thereon, in the form of a film, to the gases in the engine to form a combustible mixture, means being provided to vary the extent of movement of said member to vary the amount of the exposed film. The invention further consists in' the several features hereinafter set forth and more particularly defined by claims at the conclusion hereof. In the drawing Fig. 1 is a vertical sectional view of an internal combustion engine equipped with apparatus for carrying out the method;

Fig. 2 is a detail plan view of a part of the head; I

Fig. 3 is a detail sectional view taken along the line 3-3 of Fig. 1;

Fig. 4 is a detail sectional view taken on the line 44 of Fig. 3;

Fig. 5 is a detail perspective transfer member;

Fig. 6 is a detail view, partly in section, of part of the operating mechanism for the fuel-feeding member;

Fig. 7 is a detail view showing certain modifications of the operating mechanism for the fuelfeeding member.

The invention is shown applied to a two cycle, crank case compression, port-scavenging engine, but it may be used in connection with an engine of the two or four cycle type.

In the drawing the numeral 9 designates the engine cylinder, 10 the piston working therein, operatively connected by the connecting-rod 11 to crank shaft 12 journalled in the crank case 13, the piston at the upper end of its stroke uncovering the intake ports 14 to allow the air charge to enter therein and during its firing stroke compressing said chargeand finally, near the end of its down or inner stroke, uncovering the exhaust ports 15 and thereafter the scavenge inlet view of the fuel ports 16 to allow a new charge of air, compressed v in the crank case, to-fiow therefrom through transfer port 17 and ports 16 into the cylinder to purge the same of exhaust gases and fill it with a fresh charge of air which is compressed by the piston on its succeeding up stroke in the space formed between the piston, cylinder and cylinder head 18.

A fuel-carrying member 19, preferably in the form of a rotary disk provided with a stem 20 is mounted in the cylinder head and is moved to transfer fuel from a source of supply to the combustion space.

The member or disk 19 seatson a plug or casing 21 mounted in a bore in the head in a pressure-tight manner, said casing havinga fuel feed passage 22 formed therein and also a jacket space 23 for a suitable cooling fluid, the stem 20 also extending through said casing and projecting beyond the same. The plug 21 is preferably so arranged in the head that the outer face of the disk comes as closely as possible to the cooled face 24 of the head so as to be cooled thereby and so that the upper face of said disk is alined or its outer edge adjacent the combustion chamber is substantially alined with the minimum clearance space formed between the topof the piston and that portion of the head facing the same. The plug is provided with a', groove or space 26 communicating with the top face of the disk adjacent the piston and with a passage 2'7 forming the combustion chamber, which may be enlarged or extended to provide the necessary clearance for the compression pressure desired.

Liquid fuel is supplied to the passage 22 through piping 28 connected with a supply tank 29. The fuel may be supplied under a gravity head but to provide for all conditions of engine operation it is preferred to supply the fuel under a slight pressure, for example, one to ten pounds, by means of an air pump 80 driven by the engine and delivering compressed air through the discharge pipe 31 to the tank 29, this pressure being under the control -of the operator through any suitable pressure regulator valve mechanism 32, for example, a spring-closed needle valve 33 controlling unloading of the air pressure through passage 34 and atmospheric ports 35, its spring 36 being adjusted by a hand-nut 37.

While the disk 19 is normally urged to its seat against the casing 21 by the pressure in the cylinder, a light spring 38 may also be used to keep said disk against its seat. The fuel deposited from the passage 22 on the disk is carried around on the same between the seating surfaces as a very thin layer or film as the disk is rotated until the film is exposed at the opening 26 of the combustion chamber. The movement of the disk to accomplish this may be an oscillatory one or it may be a step by step rotary motion variable in extent to vary the area of the film to suit the speed and load conditionsof the engine. For an oscillatory movement the stem of the disk may have a bevel gear 39 mounted thereon, meshing with a segmental bevel gear 40 mounted on an ososcillatory shaft 41 carrying a lever 42 which has an arcuate slot 43 formed therein in which a bolt 44, passing through the upper end of a tappet rod 45, is adjustably secured by a nut 46, said rod 45 having a jointed lower end 47 hinged at 47 to'permit the upper portion thereof to be moved so as to vary the effective length of the lever arm 42 and thus vary the extent of oscillatory movement of the gear 39 and hence the disk 19. The lower end of the tappet member carries a roller 48 acted upon by a cam 49 suitably mounted on the shaft 12, and which causes an upward movement of the tappet and consequently a rotary movement of the disk, the parts being returned by a spring 48' acting on said tappet. The movement of the tappet rod may be varied to vary the timing of the disk movement or to vary the extent of this movement by providing adjustable stop-nuts 50 on the lower end 47 cooperating with an adjustable screw stop member 51 on the engine frame, whereby the roller 48 may be raised or lowered to be engaged by the cam later or sooner in the cycle of the engine.

Where an intermittent step by step rotation of the disk is desired the arrangement may be modifled, as shown in Fig. '7, by having the tappet member, previously described, associated with a lever arm 52, associated with one of the rotary members of a one-way roller clutch 52', the other rotary member of said clutch being mounted on a shaft 53 carrying a spiral gear 54 meshing with a spiral gear 55 on the stem 20. No details of the roller clutch are here given as the same may be of any suitable or known construction and as an example of one such clutch mechanism reference air in the combustion chamber, is subjected to the vaporizing and heating action of the gases therein and is gasified thereby to form the charge which on burning expands during the down stroke, doing work against the piston. It is to be noted that as the piston nears the end of its compression stroke the air undergoing compression is I squeezed between the piston and head in the space 25 and is forced therefrom over the surface of the exposedfilm on the disk into the combustion chamber 27.

The time at which the film is delivered to the combustion chamber of the engine will depend upon the cycle used,whether constant volume or partly constant volume and partly constant pressure,the compression pressure and the speed. The disk-may start to deliver its charge at the beginning of compression and continue to the end thereof in a two cycle, or it may be delayed until later, or it may possibly start during the suction stroke in a four cyc1e, or be delayed until later; Volatile fuels, such as gasoline or its sub-' stitutes, may be used in the engine under higher compression pressures than in carburetor type engines because introduction of the fuel may be delayed to avoid detonation. Heavier fuels with increased compression may be used, the heat of the air serving to vaporize such fuel and the thin filmlike condition thereof permitting ready vaporization. Ignition of the charge may be in any of the well known ways, such as spark, hot plug 56 or heat of compression, depending upon the amount of compression used.

It is to benoted that the passage 22 may be located farther away from the space 26, where, I

the angular movement of thedisk 19 is suificient to accomplish the feeding of the required amount of fuel to the engine on the oscillatory movement of said disk, and that where a step by step rotamovable surfaces formed by the disk 19 and its seat are normally in sealing engagement with each other, due principally to capillarity and also to some extent the oiliness of the fuel and its viscosity, the fuel from the passage 22 which wets the disk 19 is carried between these surfaces and formed into a film, which is carried on said disk to a position for exposure to the combustion supporting gases and readily forms a combustible mixture therewith.

I desire it to be understood that this invention is not to be limited to the specific details hereinbefore set forth except insofar as such limitations are included in the claims. or necessitated by the prior art.

What I claim as my. invention is:

l. The method of feeding liquid fuel to and forming combustible mixtures in internal combustion engines which consists in delivering the liquid fuel to the combustion chamber of the engine during the compression period in the form of anon-kinetic film and passing air under compression over said film to vaporize the 'same and form a combustible mixture therewith.

2. The method of feeding liquid fuel to and forming combustible mixtures in internal combustion engines which consists in delivering the liquid fuel to the combustion chamber of the engine during the compression-period in the form of a non-kinetic film, passing air under compression over said film to vaporize the same and form a combustible mixture therewith, and varying the area of the exposed film to suit the load conditions of the engine.

3. In an internal combustion engine, the combination with the combustion chamber, of a movable fuel delivery member, means for supplying liquid fuel to said member, means cooperating withsaid member to form a film of liquid fuel thereon, and means for moving said member to expose the liquid fuel film thereon to the gases in said combustion chamber.

4. In an internal combustion engine, the combination with the combustion chamber, of a rotatable fuel delivery member, means for supplying liquid fuel to said member, means against which said member seats and cooperating therewith to' form a film of liquid fuel thereon, and

means for moving said member to expose the liquid fuel film thereon to the gases in said combustion chamber.

5. In an internal combustion engine, the combination withthe combustion chamber, of a rotatable fuel delivery member, means for supplying liquid fuel to said member, means against which said member seats cooperating therewith to form a film of liquid fuel thereon, means for rotating said member to expose the fuel film thereon to the gases in said combustion chamber,

and means for varying the extent and time of rotation of said member.

6. In an internal combustion engine, the combination with the combustion chamber, of a rotatable fuel delivery member, means for supplying liquid fuel to said member, means against which said member seats cooperating therewith to form a film of liquid fuel thereon, and means for imparting a variable step by step rotation to said member in cyclic synchronism with the engine to expose the fuel film thereon to the gases in said combustion chamber.

'7. In an internal combustion engine having an engine cylinder and a piston working therein, the combination of a chamber in restricted communication with said cylinder, and means including relatively movable members adjacent the restricted entrance to said chamber from the cylinder for feedingthe fuel thereto in the form 'of a non-kinetic film 8. The method of feeding liquid fuel to and" tating said member to expose the fuel film thereon to the gases in said combustion chamber, and

means for varying the extent of rotation of said member.

10. In an internal combustion engine, the combination of a cylinder, a piston working in said cylinder, a chamber adjoining and in communication with the end of the cylinder, and a movable fuel carrying member mounted in the head end of the cylinder for exposing fuel in the form of a non-kinetic film to gases passing between said cylinder and chamber, and means for moving said member to expose said film.

11. Fuel feeding means for oil engines comprising two relatively movable members, having adjoining surfaces of appreciable area communicating with a combustion chamber, means to supply fuel between the aforesaid surfaces, and means for producing relative movement between said members to expose a fuel covered surface to the air compressed Within the combustion chamber.

12. Fuel feeding means as in claim 11, and means to regulate the area of surface exposed.

13. The method of supplying liquid fuel to internal combustion engines which comprises delivering the liquid fuelinto the space between relatively movable surfaces, which space communicates with the engines combustion chamber, thereby to distribute it in a thin film over such surfaces, and then exposing a film-covered surface to highly compressed air in the combustion chamber.

14. The method of controlling the operation of internal combustion engines which consists in delivering the liquid fuel into the space between LOUIS o. FRENCH. 

